Day 2
Hour 1
As an introduction to making a battery, watch a clip from Breaking Bad (Season 2 episode 9 start at 35:20 to 40:45). Even though batteries are designed to carefully release energy slowly, we need to remember that the underlying chemistry involves powerful redox reactions. As Boeing recently learned, efficient lightweight high capacity batteries must be handled carefully. High capacity batteries tend to use highly exothermic redox reactions which if not carefully contained can literally blow up. Boeing's newest airliners were grounded for months as they figured out why their backup batteries on the planes caught fire! These lithium ion batteries are essentially the same as the ones in your cell phone. One of the main problems with these batteries is the liquid electrolyes inside. They are non-water based since lithium reacts with water and tend to use flammable solvents. Puncturing the cell or overcharging can result in fires and explosions. Recently, a company has begun developing a solid state electrolyte to get around this problem. Watch the video on this site where the CEO of this company explains how the new technology that may be the solution to our immediate batteries needs for cars and phones.
In preparation for building a battery, study this online animation of a galvanic cell.
Battery Lab - including writing the battery lab report
Review Redox homework
Hour 2
Use Molecular Workbench to run the Virtual Battery lab (if you forget how to get into MW or don't have an account yet, follow these Instructions for creating an account in Molecular Workbench). Be sure to answer all the questions and include both partners on the final report if you work in pairs.
If you still have questions about how a battery works, you can watch the ChemGuy Video on the Daniel Cell (Zn|Zn+2||Cu+2|Cu) which is the one we will be building tomorrow. There are also some good descriptions online at Battery Basics (stop reading at "The Fuel Cell") and Galvanic Cells (stop reading at "Cell description conventions"). If you still want more, check out the Khan Academy lesson on Galvanic cells.
Hour 1
As an introduction to making a battery, watch a clip from Breaking Bad (Season 2 episode 9 start at 35:20 to 40:45). Even though batteries are designed to carefully release energy slowly, we need to remember that the underlying chemistry involves powerful redox reactions. As Boeing recently learned, efficient lightweight high capacity batteries must be handled carefully. High capacity batteries tend to use highly exothermic redox reactions which if not carefully contained can literally blow up. Boeing's newest airliners were grounded for months as they figured out why their backup batteries on the planes caught fire! These lithium ion batteries are essentially the same as the ones in your cell phone. One of the main problems with these batteries is the liquid electrolyes inside. They are non-water based since lithium reacts with water and tend to use flammable solvents. Puncturing the cell or overcharging can result in fires and explosions. Recently, a company has begun developing a solid state electrolyte to get around this problem. Watch the video on this site where the CEO of this company explains how the new technology that may be the solution to our immediate batteries needs for cars and phones.
In preparation for building a battery, study this online animation of a galvanic cell.
Battery Lab - including writing the battery lab report
Review Redox homework
Hour 2
Use Molecular Workbench to run the Virtual Battery lab (if you forget how to get into MW or don't have an account yet, follow these Instructions for creating an account in Molecular Workbench). Be sure to answer all the questions and include both partners on the final report if you work in pairs.
If you still have questions about how a battery works, you can watch the ChemGuy Video on the Daniel Cell (Zn|Zn+2||Cu+2|Cu) which is the one we will be building tomorrow. There are also some good descriptions online at Battery Basics (stop reading at "The Fuel Cell") and Galvanic Cells (stop reading at "Cell description conventions"). If you still want more, check out the Khan Academy lesson on Galvanic cells.